Release coatings are useful for many applications whenever it is necessary to provide a surface or material which is relatively non-adherent to other materials which would normally adhere thereto. Silicone paper release compositions are widely used as coatings which release pressure-sensitive adhesives for labels, decorative laminates, transfer tapes, etc. Silicone release coatings on paper, polyethylene, Mylar and other such substrates are also useful as non-stick surfaces for food handling and industrial packaging applications.
For example, when labels are coated with an adhesive, it is desirable that the paper backing be easily peeled away from the label when it is ready for use, yet the adhesive quality of the label should not be reduced by peeling it away from the substrate upon which it was stored. The same principle applies to certain types of adhesive tapes which come in rolls. It is necessary that the tape unroll easily and still maintains its adhesive characteristics. This can be accomplished by coating the non-adhesive side of the tape with a silicone release composition which will come into contact with the adhesive as the roll of tape is manufactured.
Substrates coated with standard silicone release formulations have a relatively high coefficient of friction. When a coated substrate is transported on static steel rolls, obstruction of the rolls and deformation of the coated substrate can occur, due to the high coefficient of friction. The formulation of this invention reduces the coefficient of friction to a very low value, while substantially maintaining the release properties of the silicone release coating. This allows transport of a fully effective silicone release coated substrate on, for example, static steel rolls without any problems.
Most silicone release coatings have a glossy surface. An additional feature of the silicone release coatings obtained from the invention is a mattee finish surface, which is advantageous for use in applications such as decorative films, as the matte finish allows the adhesive to be repositioned.